An open string left ringing against a fretted grip. Because it costs no finger, it sounds a note the closed shape has none left for -- a tension on top, or a pedal root underneath. Either a familiar grip with open strings added, or a shape so sparse the open strings carry the chord. These belong to their key rather than to a shape, so D, A, G and E have many and Eb a handful.
C6 is C, E, G and A — C with a major sixth added on top.
It sounds warm, and finished without being sweet. It closes a tune as firmly as the triad does but without the maj7’s shine, which is why so many standards end on one.

| C | E | G | A |
|---|---|---|---|
| 1 | 3 | 5 | 6 |
Tonic — an ending chord.
Also written Cmaj6, CM6 or C major 6. The same chord either way; which spelling you meet depends on who wrote the chart.
An open string left ringing against a fretted grip. It costs no finger, so it can sound a note the closed shape has none left for: a tension on top, or a pedal root underneath.
These belong to their key rather than to a shape: they cannot be moved up the neck. D, A, G and E have many; E♭ has a handful.
C6 has 6 of them, on strings 6-5-4-3-2-1, strings 6-5-4-3-2, strings 5-4-3-2-1 and strings 6-4-3-2-1, from the 2nd fret up to the 7th — every inversion the chord has: E in the bass and A in the bass. The one to learn first is the E shape at the 3rd fret, which is the easiest grip here.
Start with x32210 — no barre and 1 open string. 1 of the 10 shapes here sits in open position. 4 of the 10 need a barre. Together they cover the neck from the 1st fret to the 15th.
| Frets | Where | Bass | Top | Hand |
|---|---|---|---|---|
| x32210 | open position | C, root position | E | 1 open string |
| x35555 | 3rd fret | C, root position | A | barred |
| x75555 | 5th fret | E, 1st inversion | A | barred |
| 877555 | 5th fret | C, root position | A | barred |
| 575585 | 5th fret | A, 6th in the bass | A | barred |
| 8x798x | 7th fret | C, root position | G | all fretted |
| 8-x-10-9-10-8 | 8th fret | C, root position | C | all fretted |
| 8-10-x-9-10-8 | 8th fret | C, root position | C | all fretted |
| x-x-10-12-10-12 | 10th fret | C, root position | E | all fretted |
| x-15-14-14-13-x | 13th fret | C, root position | C | all fretted |
The same notes rebuilt from scratch give 5 shell, 15 drop 2 and 10 drop 3 voicings, each on its own page.
Tensions. A shell of C6, root, third and seventh, leaves a string free, and the tones that belong over it are the 9 (D) and the #11 (F#).
How you get to it. The turn that lands on C6 is Dm7 to G7 — the ii and the V of C — and G7 shares its third and seventh with Dm7, so the hand barely moves between them.
In which keys. Every note of C6 belongs to C major (the I), D minor (the ♭VII), E minor (the ♭VI), F major (the V), G major (the IV) and A minor (the ♭III).
Every note of C6 is in C major pentatonic, C major, C lydian, C mixolydian and C lydian dominant.
Change one note of C6 and you have C (drop the sixth), Cmaj7 (the sixth becomes a major seventh), Cm6 (the major third becomes a minor third), Cadd9 (the sixth becomes a ninth), C69 (add the ninth) or C7 (the sixth becomes a flat seventh).
C6 is a major chord — root, major third, fifth. Major chords on every root.
On C6’s sound and use this page follows Mark Levine, The Jazz Piano Book (Sher Music, 1989). The shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.